Support system for solar panels with modified joists

ABSTRACT

A foldable, bi-directional, two-tier panel support system includes a wide variety of different configurations both for the lower support joists and the upper panel rails. The overall array is provided with additional strength through the use of various diagonal and lateral supports running between adjacent upper panel rails. Additional panel loads can be accommodated by extended longitudinal beams on tilt brackets, and additional bracing attached thereto.

PRIORITY INFORMATION

The present Utility application claims priority as acontinuation-in-part application from U.S. Provisional PatentApplication Ser. No. 61/539,653, filed Sep. 27, 2011 (now abandoned);and priority as a continuation-in-part of U.S. patent application Ser.No. 13/115,506, filed May 25, 2011 (currently pending), which is acontinuation-in-part of U.S. patent application Ser. No. 12/686,598,filed Jan. 13, 2010 (now issued as U.S. Pat. No. 8,256,169), which is acontinuation-in-part of U.S. patent application Ser. No. 12/567,908,filed Sep. 28, 2009 (now issued as U.S. Pat. No. 8,240,109), which is acontinuation-in-part of U.S. patent application Ser. No. 12/383,240,filed Mar. 20, 2009 (now issued as U.S. Pat. No. 8,316,590). Referencesmade to all listed applications, and their contents, are incorporatedherein by reference in their entirety.

FIELD OF THE INVENTION

This invention relates in general to support systems for panels andpanel-like structures, such as solar energy collection systems. Moreparticularly, the present invention is directed to a ground-supportedmounting system for an array of photovoltaic panels, and a method ofassembling the same for activation. The panel support system can includea bi-directional, two-tier matrix having specifically configuredsupport, and bracing elements arranged for attachment to a tiltingground substrate supported system.

BACKGROUND OF THE INVENTION

A standard photovoltaic (solar) panel array includes a plurality ofsubstantially parallel solar panels 12 (FIG. 3), optimally arranged forconverting light incident upon the panels to electricity. Various panelsupport systems are used for attachment to roofs, free-field ground(supported by a ground substrate, such as a concrete pad) racks (14, 15in FIG. 1) or tracking units. Typically, these support systems arecostly, labor-intensive to install, heavy, structurally inferior, andmechanically complicated.

Placing the photovoltaic or solar panels 12 on the support structure 10can be very difficult, as can wiring of the solar panels for arrayactivation. Further, some large solar panels tend to sag and flex,thereby rendering the panel mounting unstable. Unstable panelarrangements also jeopardize the integrity of the wiring arrangement,which is necessary for the photovoltaic panels to be useful.

All of these difficulties are exacerbated when the solar panel array ismounted at an angle, such as 45° from horizontal. Tilting supportsystems (16, 14 in FIGS. 1 and 3), whether they are free-field groundracks or variable tilt racks mounted on buildings, are examples ofinstallations that can be particularly difficult when mounting solarpanel arrays. Examples of conventional tilt-mounted configurations aredepicted in FIGS. 1-3, 4 a, 4 b. Most structural, bi-directional arraysused for mounting panels are designed so that optimum stresscharacteristics occur when the support array is in a horizontalposition. Placing such an array at an angle to horizontal introduces anadditional set of stresses that can degrade the structural integrity ofthe array under any number of conditions. Even if the tilt support forthe array is adjustable so that the array can be mounted to the tiltsupport in a horizontal position, the stresses are still introduced oncethe tilt support is moved so that the array is at an angle to theoriginal horizontal position. Also, in many cases, the tilt support(such as tilt bracket 16) is not adjustable after it is originallyinstalled. Consequently, the panel array must be mounted under theadditional stresses created by placing the panel array in anon-horizontal position. Very often, this is difficult, time-consuming,and even dangerous.

With advanced rigging techniques, it is possible to effect safeinstallation of support matrices or arrays 10 at non-horizontal angles.However, this is normally done using special rigging or installationequipment. Once this equipment is removed, the stresses encountered whenat the non-horizontal mounting angles begin to take effect. Thesestresses are increased by environmental conditions, such as the wind,rain or snow, may ultimately serve to degrade certain structural numbersof the support matrix. The amount of degradation depends upon theoverall external force and weight of the panel support matrix and theangle at which the support matrix is ultimately placed in reference tothose external environmental forces. It has been discovered that tubularstructures (17 and 18 in FIG. 2 a) especially those forming the lowersupport joists (11, 13 in FIGS. 2 a, 2 b), can be especially vulnerableto destructive stresses developed by a non-horizontal mounting of thepanel support matrix.

One traditional panel support system includes off-the-shelf metalframing channels (upper members 19 constituting panel rails 15 in FIGS.2 a, 2 b) having a C-shaped cross-section, such as those sold under thetrademarks UNISTRUT™ or BLIME™, improvised for use as upper and lowersupport members forming the bi-directional support matrix. Thephotovoltaic (solar) panels 12 or other panel-like structures aredirectly secured to the support members and held in place by panel clipsor panel holders in a wide range of sizes and shapes. The panel clipsserve as hold-down and grounding devices to secure the panel against thecorresponding top support member in a spaced relationship. The panelclips are positioned and attached about the panel edges once each panelis arranged in place on the bi-directional support matrix.

For a conventional free-field ground rack system (for mounting solarpanels) as shown in FIGS. 1-3, vertical support elements, such asI-beams 14, are spaced and securely embedded vertically in the ground orsubstrate. Tilt-mounting brackets 16 are installed at the top of eachI-beam, and each tilt-mounting bracket is secured to the I-beam suchthat a tilt bracket flange or top section extends above the I-beam at a90° angle to the side of the tilt-mounting bracket as best seen in FIGS.1 and 3. As shown in this case, two UNISTRUT™ joists 13 span thetilt-mounting brackets 16 and are secured thereto. As seen in FIG. 2 b,UNISTRUT™ upper panel rails 15 are positioned across and fastened to thelower support joists 13. To secure each upper panel rail 15 to thecorresponding lower support joists 13, a bolt (through a bolt hole madein the rail sidewall) attaches to a threaded opening in a transversenut-like plate slideably mounted inside the channel of the UNISTRUT™rail, so that the nut-like plate engages and tightly secures against theupper flange of the joist's C-channel 11 as seen in FIG. 2 a.Importantly, the width of the plate is slightly less than the width ofthe channel, so that the plate can be slideably adjusted in the channel,without the plate rotating therein.

Once the bi-directional, two-tier support system 10 is assembled, eachsolar panel 12 is mounted on a lower portion of conventional panelholding clips which are secured to the upper panel rails about theperimeter of each panel. The other portion of the panel clips is put inplace and tightened. This installation process is usually inaccurate andtime-consuming, even with expensive, skilled installers.

Another conventional example of a panel support system is shown in U.S.Pat. No. 5,762,720, issued to Hanoka et al., which describes variousmounting brackets used with a UNISTRUT™ channel. Notably, the Hanoka etal. patent uses a solar cell module having an integral mountingstructure, i.e. a mounting bracket bonded directly to a surface of thebackskin layer of a laminated solar cell module, which is then securedto the channel bracket by a bolt or slideably engaging C-shaped members.Other examples are shown in U.S. Pat. No. 6,617,507 issued to Mapes etal., U.S. Pat. No. 6,370,828 issued to Genschorek, U.S. Pat. No.4,966,631 issued to Matlin et al., and U.S. Pat. No. 7,012,188 issued toErling. All of these examples of conventional systems are incorporatedherein by reference as background.

Notably, existing conventional support systems require meticulouson-site assembly of multiple parts performed by expensive, dedicatedfield labor. Assembly is often performed in unfavorable workingconditions, i.e. in harsh weather and over difficult terrain, withoutthe benefit of quality control safeguards and precision tooling.Misalignment of the overall support assembly often occurs. This canjeopardize the supported solar panels 12, or other supported devices.Further, wiring of the solar panels, once electrically connected, isalso problematic in conventional systems.

Proper spacing of the photovoltaic (solar) panels 12 is important toaccommodate expansion and contraction due to the change in weather. Itis also important that the panels are properly spaced for maximum use ofthe bi-directional area of the span. Different spacing may be requiredon account of different temperature swings within various geographicalareas. It is difficult, however, to precisely space the panels on-siteusing existing support structures without advanced (and expensive)technical assistance.

For example, with one of the existing designs described above (withreference to FIGS. 2 a and 2 b), until the upper panel rails are tightlysecured to the lower support joist, each rail is free to slide along thelower support joists and, therefore, will need to be properly spaced andsecured once mounted on-site. Further yet, since the distance betweenthe two support joists is fixed on account of the drilled bolt holesthrough the rails, it is preferred to drill the holes on-site, so thatthe lower support joists can be aligned to attach through thepre-drilled attachment holes of the tilt bracket. Consequently, theoperation of drilling the holes on-site requires skilled workers, andeven with skilled installation, might still result in misalignment ofthe support structure and/or the solar panels supported by thatstructure.

One major advantage of free-field ground racks, such as the tiltbrackets (14, 16) depicted in FIGS. 1, 2 a and 3, is that very largesolar panel arrays can be supported. The space that permits theelaborate support structure of a free field support, such as thosedepicted, usually means that a very large solar array can beaccommodated, at least in the space available. Unfortunately, there arelimitations other than the available ground space.

In particular, the tilt bracket 16 in conventional arrangements canaccommodate only two lower support joists 20. This substantially limitsthe size of the solar array that can be accommodated. Conventionally,larger arrays require additional ground or substrate installations tosupport additional tilt brackets. This can be an expensive, an oftenintolerably awkward option for creating substrate or ground support forlarge solar panel arrays.

Even if arrangements can be made to support larger solar panel arrayswith expanded tilt bracket capacity, new problems arise. For example,new sets of stresses are introduced by the larger array when secured toits non-horizontal position provided by the tilt brackets. Thesestresses have been examined, and results indicate increased arraywarping or deflection, especially over time. This can lead to a veryunstable arrangement for holding panels.

It is important to note that misalignment difficulties are exacerbatedby the flexing of the support array 10, and the sagging permitted by theflexibility of the panels. The sagging of the panels can cause thepanels to work out of their clips or holders, whether they are securedby separate holding clips or part of the overall structure of the uppersupport rail. Improper installation, which occurs frequently inconventional systems, can lead to dislocation of the panels due tosagging and/or changing environmental conditions and stresses. A widevariety of different mounting positions and array arrangements alsoexacerbate the stability problems caused by panel sagging anddeflection. Further, certain mounting positions will make the panelsmore vulnerable to environmental disruptions created by wind andprecipitation. Freeze-thaw cycles can also be a major factor. All ofthese variables are further complicated by non-horizontal mounting ofthe panel support array.

Existing panel clips or holders are generally configured to avoid damageto the solar panel framework and to facilitate easy installation, oftenat the cost of panel security. Once panels loosen, the integrity of theelectrical connections (in particular ground connections) between thepanel and the supporting panel rail 30 is compromised. While a break ofthe electrical circuit is not necessarily the immediate result,resistance will increase at the loosened connections, thereby degradingelectrical efficiency. If such a condition persists, degradation of themetal at the electrical contact points can also occur, thereby evenfurther degrading the electrical system.

Conventional panel clips or holders can be problematical for a number ofreasons. Firstly, installation for use of the clips is verytime-consuming, even for skilled installers. If the clips are notsufficiently tight, loosening of the panels will certainly occur. If theclips are overly tight, the panels can be deformed or otherwisedegraded. Further, the cost of numerous panel clips, as well as thegaskets that are used therein, can substantially increase the overallequipment costs, as well as add adding to the installation costs.

The arrangements depicted in FIGS. 1, 3, 4 a, 4 b, and 5 a are limitedto rather constrained configurations. In particular, only two supportjoists 20 can be mounted on the ground support and tilt bracketconfiguration (14, 16). This severely limits the size and shape of thesolar panel arrays that can be used with this type of ground support. Ifsufficient space exists and the ground support and tilt bracketconfiguration (14, 16) are sufficiently strong, then larger panel arrayswith more than two support joists 20 would be highly desirable.

Therefore, a need exists for a low-cost, uncomplicated, structurallystrong support system and assembly method, so as to optimally positionand easily attach a plurality of photovoltaic panels while meetingarchitectural and engineering requirements, especially with regard todurability. Likewise, there is an urgent need for a non-horizontalmounted solar panel system that will maintain the security of themechanical connections of the solar panels to panel rails despite theflexing of the panels (and support structure) caused by gravity,vibration, and the other environmental factors previously discussed.

At present, none of the conventional systems has these capabilities.With this invention, an improved panel support system is achieved havinga more precise configuration in the field, without requiring extensiveand extra work at the installation site. The use of such an improvedsystem would facilitate easy placement of solar panels onto the supportstructure. Further, a simple panel holding arrangement could be usedwithin the overall concept of the system, while providing securemechanical and electrical connections. The shipping configuration of theimproved support system would be such so as to be easily handled intransit while still facilitating rapid deployment. With this invention,rapid deployment on a ground support and tilt-mounting bracket would notsacrifice stable support for the panels. Rapid deployment includes rapidmechanical and electrical connections of the panels to panel supportrails in a manner that keeps the panels electrically and mechanicallysecure, despite panel flexing caused by the several factors discussed.

SUMMARY OF THE INVENTION

It is a primary object of the present invention to improve uponconventional photovoltaic solar panel systems, especially with regard toassembly, wiring, and overall installation durability.

It is another object of the present invention to provide a support andinstallation system for solar panels in which the panels andinstallation site are less likely to be damaged during installation.

It is a further object of the present invention to provide a supportsystem for solar panels that is easily installed on-site while stillresulting in a precise configuration for purposes of mounting the solarpanels.

It is an additional object of the present invention to provide a solarpanel support system that can be assembled very quickly on-site.

It is still another object of the present invention to provide a solarpanel support system that can achieve close tolerances during fieldinstallation without the necessity of skilled labor at the installationsite.

It is still an additional object of the present invention to provide asolar panel support system which can be easily adapted to a wide varietyof solar panel array sizes and shapes.

It is yet another object of the present invention to provide a solarpanel support system which minimizes the necessity for precisemeasurements at the installation site during installation.

It is still an additional object of the present invention to provide asolar panel support system that can be precisely configured to aspecific ground environment.

It is another object of the present invention to provide a supportsystem for solar panels and other panel-like structures in whichdegradation caused by metal-to-metal contact is substantially reduced.

It is again another object of the present invention to provide a supportsystem for panel-like structures in which accommodation is made formovement caused by wind, changes in temperatures, or other environmentalconditions.

It is again another object of the present invention to provide aflexible arrangement for adapting a solar panel support system toaccommodate a wide variety of different panel configurations.

It is still an additional object of the present invention to provide asolar panel mounting system that can accommodate easy installation andremoval of panels on adjacent frameworks.

It is still a further object of the present invention to provide afolding solar panel support system in which rotation of structuralmembers with respect to each other can be advantageously controlled.

It is yet another object of the present invention to provide panel clipsfor a solar panel support structure which allow easy installationwithout interfering with adjacent panels.

It is still an additional object of the present invention to provide acollapsible panel support system wherein deployment of the supportsystem using rotating connection members can be precisely adjusted.

It is again a further object of the present invention to provide a panelsupport structure which integrates easily in a wide range of mountingsites, and needs minimal mounting or deployment time.

It is still another object of the present invention to provide a supportsystem for panels or panel-like structures for a wide range of uses,positions and structures.

It is again an additional object of the present invention to provide apanel support system in which the relative rotation of the structuralmembers to each other, when deploying the support system, is carefullycalibrated and controlled without adjusting or tightening of therotating joints at the installation site.

It is still another object of the present invention to provide a panelsupport system which can be easily fixed to a “hard” mounting groundsupport using bolts, without causing damage to the panel support system.

It is yet another object of the present invention to provide a panelsupport system that can be easily deployed or removed by rotatingintersecting structural members, without fouling, jamming or binding atthe intersections of the structural members.

It is again an additional object of the present invention to provide apanel mounting system which facilitates quick, secure mounting of thepanels once the support system is deployed, without complexpanel-holding devices.

It is yet another object of the present invention to provide a panelsupport system that can accommodate flexing, sagging and otherdeformation of the panels while maintaining a secure connection thereto.

It is yet a further object of the present invention to provide a panelmounting system which facilitates easy electrical connections to thepanels.

It is again an additional object of the present invention to provide apanel support system that facilitates secure and easy connection anddisconnection of electrical wires running throughout the system.

It is still another object of the present invention to provide a panelsupport system that facilitates secure electrical connections betweenthe panels and the supporting panel rails under a wide variety ofconditions and circumstances.

It is again a further object of the present invention to provide a panelsupport system that accommodates secure support when positioned in anon-horizontal position.

It is yet another object of the present invention to provide a panelsupport system that reduces degradation due to metal fatigue, even whenthe support system is exposed to extreme weather conditions when mountedin a non-horizontal position.

It is again a further object of the present invention to provide a panelsupport system that aligns and installs easily to substrate supportinstallations.

It is still an additional object of the present invention to provide apanel support system that holds up to the accumulation of snow and/orwater, as well as shifting forces and torque caused by wind,particularly when the support system is mounted in a non-horizontal(i.e. inclined) position.

It is still another object of the present invention to provide a panelsupport system that is particularly effective with ground supported,tilt bracket installations.

It is the overall goal of the present invention to provide acomprehensive panel mounting system that facilitates rapid, secureinstallation, including deployment of the panel support structure,placement of the panels on that support structure, and wiring of thepanels for activation.

These and other goals and objects of the present invention are achievedwith a support system for an array of parallel panels, wherein thesupport system includes vertical tilt brackets supported by anunderlying substrate. This support system also has a foldable supportarray which includes a connection interface for each vertical tiltbracket supporting at least two upper panel rails at connection points,and at least two diagonal supports arranged between adjacent upper panelrails. The foldable support array is arranged so that the upper panelrails are parallel to each other in a deployed position and iscollapsible so that the upper panel rails, and at least one of thediagonal supports are substantially longitudinally aligned with eachother in a package suitable for motor road transport.

BRIEF DESCRIPTION OF THE DRAWINGS

Having generally described the nature of the invention, reference willnow be made to the accompanying drawings used to illustrate and describethe preferred embodiments thereof. Further, the aforementionedadvantages, and others, will become apparent to those skilled in thisart from the following detailed description of the preferred embodimentswhen considered in light of these drawings, in which:

FIG. 1 is a perspective view of an assembled conventional field groundrack support system for securing a plurality of solar panels;

FIG. 2 a is a side view of a conventional tilt bracket mount with priorart C-shaped sectional channels secured back-to-back to form supportjoists to which upper panel rails, also shown in FIGS. 2 b, are secured;

FIG. 2 b shows an end view of prior art upper panel rails, each with aC-shaped sectional channel;

FIG. 3 is a perspective view of a previously-disclosed, inventivesupport system in a configuration as used with the instant inventionshowing solar panels arranged in a column and in a spaced relationshipthereon, wherein the support system has horizontally-aligned lowersupport joists and (relative thereto) vertically-aligned upper panelrails;

FIG. 4 a is a top plan view of the bi-directional span of the assemblyas used in the instant invention, in the open position showingvertically-aligned upper panel rails attached atop horizontally-alignedlower support joists;

FIG. 4 b is an end elevational view of the bi-directional span of theassembly shown in FIG. 4 a;

FIG. 5 a is a top view illustrating the bi-directional support frame ofthe assembly shown in FIG. 4 a collapsed to an intermediate semi-foldedposition;

FIG. 5 b is a top view depicting, in enlarged detail, the support systemin a collapsed or folded position, and in particular, a steel bearingwasher between the upper panel rail and the lower support joists, aswell as a connector for holding the lower support joist to a supportand/or tilt bracket or similar structure, i.e. held between adjacent,folded panel rails;

FIG. 5 c is a side view of FIG. 5 b depicting the steel bearing washerand the connector for holding the lower support joist to a supportand/or tilt bracket or similar structure;

FIG. 6 is an end view of a lower support joist used as part of thepresent invention;

FIG. 7 a is a top view of a support system configured with diagonalcross supports according to the present invention;

FIG. 7 b is an end view of the support system of FIG. 7 a;

FIG. 7 c is a side view of the support system of FIG. 7 a;

FIG. 7 d is a front view of a portion of the support system of FIG. 7 c;

FIG. 7 e is yet another view of a portion of the support system of FIG.7 d;

FIG. 8 is an end perspective view of the lower support joist of thepresent invention with a plurality of upper panel rails attachedthereto;

FIG. 9 is a side perspective view of a tilt mounting bracket used aspart of the present invention;

FIG. 10 is an end perspective view of the tilt mounting bracket of FIG.9;

FIG. 11 is a front perspective view of a lower support joist of thepresent invention;

FIG. 12 depicts a top perspective view of an alternative longitudinalbeam used in the configuration of the present invention;

FIG. 13 is a side view of an alternative arrangement for aground-mounted tilt structure; and

FIG. 14 is a front perspective view of an additional embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is used in the conventional environment depictedin FIGS. 1-2( b), and is an improvement upon the previously disclosedinventions depicted in FIGS. 3-5( a-c). The previously disclosedinventions by some of the same inventors are found in U.S. patentapplication Ser. No. 12/383,240 (filed Mar. 20, 2009); U.S. patent Ser.No. 12/567,908 (filed Sep. 28, 2009); and, U.S. patent application Ser.No. 12/686,598 (filed Jan. 13, 2010). All of these patent applicationsdescribe the referenced support systems. The present patent applicationrelies on all three for priority and incorporates all by reference forpurposes of providing a more complete background for the instantinvention.

FIGS. 3-5( a-c) are relied upon as disclosing the bi-directional,two-tier panel support matrix environment in which the improvements ofthe present application operate. Only a summary of the structuresdepicted in FIGS. 3-5( a-c) is provided herein, sufficient for anunderstanding of the background of the present invention. Full, detaileddescriptions of the structures depicted in FIGS. 3-5( a-c) are found inthe aforementioned, incorporated applications.

A summary of certain aspects of the previous inventions incorporatedherein by reference is provided below. In accordance with one previouslydescribed inventive embodiment constituting the background of which thepresent invention is an improvement, FIG. 3 depicts a support system 10for an array or photovoltaic array of solar panels 12, attached to aconventional, free-field vertical support arrangement (14, 16). Thesupport system 10 is constituted by a bi-directional, two-tier supportframe of horizontally-aligned lower support joists 20 andvertically-aligned upper panel rails 30 (identified as 30-1 through30-n), as also seen in FIGS. 4 a and 4 b.

For purposes of convenience when describing the new embodiments of thepresent invention, the orientation description of “upper” and “lower”will be used. While the array of support system 10 can be placed in anyorientation with respect to longitudinal or latitudinal descriptors, forthe sake of clarity the present invention always has lower supportjoists 20 and upper panel rails 30. The designation of “upper” and“lower” appears to be the most straight-forward for dealing with thetwo-tier aspects of the new invention considered herein.

The terminology “support joist” has been used previously with regard tothe prior art structural members 11, 13. The same functional type oflower structural member is designated here as “lower support joist” 20for the descriptions of both past and present inventive embodiments. Theupper structural member, previously denoted as an upper support rail 15is more accurately described by the designation “upper panel rail” 30 inthe present embodiments. This is appropriate since the structuralelement 30, denoted as an upper panel rail 30, is always located abovelower support joist 20 and constitutes the elements to which theexternal solar panels 12 are held to the support system 10.

In one alternative to the first support system 10 described above, thebi-directional, two-tier support system 10 can have the lower supportjoists 20 aligned along the length of tilt-mounting brackets 16. As aresult, upper panel rails 30 extend longitudinally, as described anddepicted in the subject previous applications. It should be understoodthat within the context of the present invention any orientation of thesubstantially perpendicular structural elements (lower support joists 20and upper support rails 30) can be used.

Further, a wide variety of different shapes, sizes and configurationsare encompassed by the concept of the present invention, which is not tobe limited by the examples provided herein. The present array of supportmembers (20, 30) can be adjusted to conform to any support structure orany “footprint” available for the deployment of solar panels 12, or anyother panel-like structure to be supported by the present invention.Further, as described infra, both the upper panel rails 30 and lowersupport joists can be modified.

The present invention is directed in particular to the use of a foldingsupport system 10 mounted on a tilt bracket ground support substructure,in particular, vertical ground supports 14 depicted in FIGS. 1, 2 a and3. The various embodiments of the present invention includemodifications to the tilt-mounting brackets 16 and the lower supportjoists 20, as well as improvements to the interface between the two.These improvements are meant to address the different stresses caused bynon-horizontal mounting in conjunction with increased panel array sizes,and various and ever changing environmental forces caused by wind, snowand rain. This increased capability is provided without degrading theconvenience of off-site pre-assembly, compact transport configuration orrapid deployment of earlier versions of the folding support system 10.

One variation of the present invention is the increased size of thetilt-mounting bracket 16 as depicted in FIG. 13. In distinct contrast tothe earlier versions depicted in FIGS. 1, 2 a and 3, the tilt-mountingbracket 16 is sized to accommodate more than two lower support joists20. As a result, longer panel rails 30 can be supported, and much largersolar panel arrays 12 can be accommodated. A major advantage is thatonly one ground support, such as concrete pier 2 shown on FIG. 13, isrequired for each tilt bracket 16. While a stronger vertical support 14is needed for the increased weight, an increase in expense for suchsupport structures is relatively minor compared to the economic benefitof the increased size of the panel array 10 being supported.

While the cost of the increased size of vertical support 14 (and itssubstrate interface 2) is not necessarily significant, the cost of theenlarged tilt-mounting bracket 16 can be. For example, tilt-mountingbracket 16 in FIG. 13 can be constituted by a structural truss,depending upon the size of panel array 10 that is to be supported, aswell as the use to which the overall structure is to be put. Forexample, the overall structure can be used as a shelter, carport, or thelike. Consequently, the overall size of the structure and the panelarray 10 can be virtually any value that can be accommodated for thesize of the installation site. Accordingly, additional variations areappropriate.

Different variations are found in the different designs depicted inFIGS. 9 and 10, as well as that depicted in FIG. 12. In both cases, alongitudinal beam 60 is located atop (or as part of) the tilt-mountingbracket 16.

In FIGS. 5 and 10 the longitudinal beam 60 forms the extended length ofthe top of the tilt-mounting bracket 16, being welded thereto. Incontrast, longitudinal beam 60 in FIG. 12 is not welded to tilt-mountingbracket 16. Rather, longitudinal beam 60 is configured to interface withcertain structural aspects of the tilt-mounting bracket 16, and can beconnected thereto in a wide variety of different techniques, such asbolting. This arrangement admits to greater flexibility, and canaccommodate a wider range of longitudinal beam 60 sizes andconfigurations. As a result, the selection of longitudinal beam 60 sizeand configuration can be made based upon the load to be placed upon theoverall structure so that a more stable structure can be obtained.

In FIGS. 9 and 10, an L-shaped channel as beam 60 is depicted. It shouldbe noted that the tilt-mounting bracket 16 can be formed with asubstantial top surface 161 or only a top edge welded so that thelongitudinal beam 60 forms the top surface of the tilt-mounting bracket16. Either variation is entirely acceptable within the concept of thepresent invention. While the longitudinal beam 60 is depicted as anL-shaped structure, other shapes are permissible within the concept ofthe present invention.

Tilt-mounting bracket 16, as depicted in FIGS. 9 and 10, has a sidewall162 and two end walls 163(a), 163(b). As depicted, the top wall 161 isconstituted by one side (top side 61) of the angle iron constitutinglongitudinal beam 60. The top side 61 of longitudinal beam 60(constituted by an L-channel with sides 61, 62) includes a slottedaperture 1611 for alignment of the lower support joists 20 of supportmatrix 10. This is used to receive connecting bolts that hold a lowersupport joist 20 to the combined longitudinal beam 60 and tilt-mountingbracket 16, which helps to align the support matrix 10 during theunfolding step. Preferably, the combined tilt-mounting bracket structure(16, 60) is made of steel, as is the lower support joist 20. The boltscan be any type currently used to hold the support matrix 10 to thetilt-mounting bracket 16. As stated, the slotted opening 1611 provides alevel of adjustability that helps facilitate easy alignment andconnection of the support matrix 10 to the tilt-mounting bracket 16 (assupported by substrate support structures 14, 2).

It has already been noted that the ground support or substrate supportstructure 2 and vertical beam 14 must be larger to accommodate theweight of an increased panel array 12. Likewise, the tilt-mountingbracket 16 is preferably modified to accommodate the greater weight anddimensions of the larger support system 10 and the panels 12 that areultimately contained therein. The tilt-mounting bracket 16 is not partof vertical support 14 in these embodiments. Consequently, it must beattached thereto. To accommodate the greater weight, a more elaborateand robust connection scheme is needed. Consequently, the sidewall 162of the tilt-mounting bracket 16 contains slotted openings 1621 (forbolts) to more easily mount it to the vertical support 14 and to providegreater structural stability. Also, increased connectivity to thelongitudinal beam 60 must be facilitated to maintain the necessarystructural stability. One such method is to use the L-shaped channel asthe longitudinal beam 60 formed as part of the tilt-mount bracket 16 asdiscussed.

In the embodiment depicted in FIG. 12, the longitudinal beam 60 isseparate from the tilt-mounting bracket 16. It must be fitted to the topof the tilt-mounting bracket 16 before support system 10 is deployed. Inthis embodiment, because longitudinal beam 60 is longer than that inFIGS. 9 and 10, mounting the longitudinal beam 60 on the tilt-mountingbracket 16 can be somewhat awkward. To facilitate easy mounting, thetilt bracket 16 of either or both of end walls 163(a) or 163(b) isprovided with an alignment finger 165. A slotted guide opening 65 on theupper surface 61 of longitudinal beam 60 allows an easy fit of thelongitudinal beam onto the tilt-mounting bracket 16. The looseness ofthe interface between slotted guide opening 65 and the alignment finger165 permits easy adjustment of beam 60 on tilt-mounting bracket 16before the final connectors are tightened, holding the longitudinal beam60 to the tilt-mounting bracket 16.

Because the present invention allows for longer longitudinal beams 60, adrawback occurs when increasing the size of the supported panel array.In particular, as longitudinal beam 60 becomes longer, more support isneeded to support longitudinal beam 60 and the overlying extendedsupport matrix 10. This is especially true at the ends of thelongitudinal beam 60, which tends to sag under the extra weight of panelsupport system 10, and its load of panels 12.

To address this situation, arcuate vertical bracing 80 is applied to thetilt-mounting brackets 16, as depicted in FIG. 9. The arcuate verticalbrace 80 is connected to the sidewall 162 of tilt-mounting bracket 16.The end surfaces 163(a), 163(b) of the tilt-mounting bracket 16 are cutso that the arcuate vertical brace 80 fits into the resulting openingsand is welded to the end surfaces 163(a), 163(b). These help support thearcuate vertical brace 80. However, other support is needed and ispreferably provided by welding the arcuate vertical brace 80 to thesidewall 162 of tilt-mounting bracket 16. While welding is preferred,other connection methods, such as bolts, can also be used. Further, anycombination of welding and bolting is also appropriate. With regard tothe design shown in FIGS. 12 a and 12 b, an angled support member 82(best seen in FIG. 8) is used for added structural support.

The use of larger panel arrays 10 on ground supported tilt-mountingbrackets 16 of this invention leads to additional weight and stresses onthe lower support joists 20, especially the tubular structures reliedupon in the aforementioned patent applications, incorporated herein byreference. These stresses are substantially increased by environmentalfactors such as wind, precipitation, and freeze cycles. Over longperiods, tubular structures which are entirely adequate for smallersupport arrays, begin to experience metal fatigue when arrayed in largerarea configurations. Even if this metal fatigue does not result inimmediate failure, additional deformation and panel loosening canresult.

The inventive solution to this difficulty is a new design for the lowersupport joist 20, depicted in FIGS. 6 and 8. This type of lower supportjoist 20 includes an upper member 21 and a lower member 22, eachsubstantially parallel to the other member. A median connecting member23 extends between the two parallel upper and lower members 21, 22.While the median connecting member 23 is depicted in FIGS. 6 and 8 asbeing perpendicular to the parallel upper and lower members 21, 22, thesupport joist 20 of the present invention is not limited thereto.Rather, the median connecting member 23 can be diagonal, extendingbetween opposite rear edges of the parallel upper and lower members 21,22. Further, the median connecting member 23 could be a curve such as anS-shaped structure, or any other structurally appropriate configuration.

The outer, opposite edges of the upper and lower members 21, 22 haveangled end portions 211, 221, respectively. The end portions can bestraight, as depicted in FIG. 6, or they can be curved. These endportions 211, 221 help strengthen the overall support joist 20. However,additional functionality can be obtained when the end portions 211, 221are curved to serve as wiring troughs, or even drainage structures.

The lower support joists 20 are connected to the supporting longitudinalbeams 60 using bolts 240 as depicted in FIG. 11. Slotted openings 24 areformed in the lower member 22 to facilitate easy connection between thepanel support system 10 and the tilt-mounting bracket with longitudinalbeam assembly (16, 60). As previously described with respect to thecited folding panel support system 10 design, only connection to onelongitudinal beam need be made in order to allow the entire panelsupport system 10 to be unfolded and then be fully deployed for completeconnection.

Besides easy connection, the slotted openings 24 also provide a meansfor draining precipitation. It is important to note that if the slottedopenings 24 prove to be inadequate for precipitation drainage, thenadditional openings (not shown) can be formed in the lower member 22 ofsupport joist 20.

An additional expedient for strengthening the lower support joist 20 andthe overall panel support system 10 is the use of diagonal braces 70 asdepicted in FIGS. 7 a-7 d. The key aspect of the cross-bracingarrangement is constituted by cross-braces 70 arranged in asubstantially A-shaped configuration. Preferably, diagonal braces 70 areU-shaped channels which rest upon lower support joists 20. Morespecifically, these diagonal braces 70 rest on the upper members 21 oflower support joists 20, on the same surfaces as upper panel rails 30.The diagonal braces 70 are arranged between panel rails 30 to form theA-shaped configuration depicted in FIG. 7 a. While a U-shape for thediagonal brace 70 is preferred, any number of other shapes can be usedto affect the necessary bracing on the lower support joist 20 of thepanel support system 10.

As depicted in FIG. 7 a, the diagonal braces 70 are connected to thelower support joists 20 at three separate points. The diagonal braces 70need to be pre-connected to the folding panel support system 10 only atthe middle portion in order to permit folding of the entire structure 10as previously described with respect to the earlier folding arrayconfigurations. The ends of each diagonal brace 70 are then bolted toone of the upper members 21 of the lower support joist 20 once theentire panel support system 10 has been unfolded for deployment.

The diagonal bracing configuration of FIG. 7 a results in lessdeflection than a support matrix 10 having only parallel bracing. It wasdiscovered that in one test case the difference in deflection was 0.2 ofan inch less with the cross-bracing of FIG. 7 a. A matter of 0.2 of aninch can be crucial when compounded with environmental factors such aswind, accumulated precipitation, freeze cycles and the like. It can bethe difference between maintaining a grip on the panels 12 (withstandard panel clips or holders) and losing that grip, therebyundermining the entire purpose of the panel support system 10.

Encompassing the aforementioned improvements, the panel support system10 of this invention still allows for off-site assembly (at a convenientstaging site) to precise engineering specifications. Once the supportmembers (30, 20) are assembled, the bi-directional span of panel supportsystem 10 can be folded or collapsed on itself, as shown with referenceto FIG. 5 a. The panel support system 10 is easily transported (by motorroad vehicle) to the installation site.

In one method of installation, the panel support system 10 is positionedand secured to at least one tilt-mounting bracket 16, via one of thelongitudinal beams 60, while still in the folded position. Afterattaching one lower support joist 20 to one of the tilt-mountingbrackets 16, using a pair of tilt-mounting bracket attachment bolts 240(as shown in FIGS. 5 b and 5 c) the bi-directional support system 10 isunfolded to the position of FIG. 4 a, and the other lower supportjoist(s) 20 is/are attached to second and/or third tilt-mounting bracket16, via second and/or third paired bolts 240 being connected to eitherof the longitudinal beam(s) 60 described above with reference to FIGS.9, 10 12 a and 12 b. This arrangement of panel support system 10provides the capability of rapid, accurate deployment, requiring littleskilled labor. Other installation methods, such as unfolding the supportsystem 10 first, and then attaching it to the tilt-mounting brackets 16,can also be used.

Another method of strengthening the overall support system 10 is to usesteel elements for both the lower support joists 20 and the upper panelrails 30. This can be especially critical when the size of the supportsystem (and the panel configuration supported) becomes even larger. Theenhanced strength of all-steel construction is also very important whenenvironmental conditions (heavy winds, snow, hail, icing, or the like)lead to increased stresses of all types. Steel elements can be used withvirtually any of the element shapes, sizes, and configurationspreviously described herein, as well as any number of shapes andconfigurations known in the structural steel arts.

While the steel-to-steel connections between upper panel rails 30 andlower support joists 20 permit the omission of insulation between thesetwo structural members, there is still the possibility of binding ifeither of the structural elements (20, 30) deforms. To address this,stainless steel bearing washer 85, as depicted in FIGS. 5 a and 5 b, areplaced between the upper panel rails 30 and the lower support joists 20at each intersection. The stainless steel bearing washers 85 facilitateeasy, controlled rotation of the upper panel rails 30 and the lowersupport joists 20 with respect to each other. This is important for easyinstallation, especially when only a single lower support joist isattached to a tilt bracket while the rest of array 10 is unfolded tocontinue the installation. Steel bearing washer 85 is sized to easilyspan adjustment slot 216 in lower support joist 20, with bolt 240passing therethrough.

Another variation of the present invention eliminates the use of panelclips or holders (120 in FIG. 3). Since framed photovoltaic panels areexpected for use with the inventive support structure 10, they can beheld to the upper panel rails 30 by means of screws (not shown) suitablefor metal connections. Most framed photovoltaic panels come withpre-drilled holes for screws, in standard configurations. These can beused with pre-drilled holes (not shown) in the upper panel rails 30 tofacilitate rapid installation of the framed solar panels 12 once thesupport array 10 is fully unfolded and attached to the underlyingsupports (tilt brackets 16). By using the pre-drilled holes in theframed solar panels 12, the expensive panel clips or holders 120 can beentirely eliminated, along with the additional steps of installing thepanel clip bottoms 100 using bolts 145 through pre-drilled holes 145′,and then placing the solar panels 12 within those clips. The topportions 100, of the clips are then tightened to hold panel 12 in place.These steps are now eliminated.

The result is a faster and more secure installation than can be achievedwith conventional panel clips 120. The elimination of the panel clips120 also removes the requirement for expertise with panel clips on thepart of the installers. Virtually no skill is required to run screwsthrough the standard holes in the framed solar panels 12 into predrilledholes (not shown) in the upper panel rails 30.

FIG. 14 depicts another embodiment of the present invention. In thisconfiguration, lower support joists 20 are constituted by C-channels,which also serve as tilt brackets 16. These support joists (i.e, tiltbrackets) 20 are connected to upright supports 16. In this particularconfiguration, the C-channel 20 constitutes both the tilt bracket andsupport joists found in previous embodiments.

The upper panel rails 30 are constituted by the type of structuralelements previously described with respect to FIG. 6. However, otherconfigurations can be used for the upper panel rails 30 in thisparticular arrangement. The attachment between the upper panel rails 30and the lower support joists 20 can be accomplished using bolts, aspreviously described. The upper panel rails 30 and the lower supportjoists 20 are separated by steel bearing washers 85 in order to preventbinding between the two structural elements when they rotate withrespect to each other.

As with earlier embodiments of the present invention, diagonal braces 70are used between adjacent upper panel rails 30. As in previousembodiments, the diagonal braces 70 are slanted opposite each other soas to suggest a roughly A-shaped configuration. Because the diagonalbraces 70 are slanted opposite each other, at least one end of one ofthe diagonal braces must be disconnected so that the overall supportarray 10 can be folded as previously described. Usually one end of oneof the diagonal braces 70 is left connected to one of the upper panelrails 30, and the other end left loose for the folding process necessaryfor transport. Accordingly, the other diagonal braces 70 can berotatably connected to panel rails 30. The diagonal braces 70 arealigned with the upper panel rails 30 when the support array 10 isfolded for transport on a motor road vehicle such as a truck.

Upon reaching the installation site, the folded support array 10 of FIG.14 will preferably be placed on a pre-existing tilt bracket 20 attachedto an existing vertical support 16. Then the entire support array 10 canbe unfolded and panel rails 30 attached to the other tilt bracket 20.The loose ends of the diagonal braces 70 are then attached to panelrails 30 as appropriate to form the configuration depicted in FIG. 14.

The diagonal braces 70, in the opposing slanted configuration aspreviously described, provide a much higher level of stiffness to theoverall support array 10 than is found in previous designs. Additionalstiffening of the overall support array 10 can be provided by auxiliarydiagonal braces 72 connected between tilt bracket 20 and upper panelrail 30. As depicted in FIG. 14, auxiliary diagonal brace 72 isconnected between the median connecting member 23 of upper panel rail 30and a lower portion of the C-channel constituting the tilt bracket 20.Auxiliary diagonal brace 72 can be configured with a surface and adrilling hole configuration to accommodate the connection betweenperpendicular pieces. Further stiffening can also be provided by lateralbraces 74, which are mounted at the ends of the upper panel rails 30.While lateral braces 74 are depicted as being attached to the lower edgeof the upper panel rail structure, other connection arrangements arealso possible. The result of the FIG. 14 configuration is a panelsupport system 10 that can withstand a wide range of stresses that mightbe caused by both extensive panel loading and environmental occurrences.

While a number of embodiments have been described as examples of thepresent invention, the present invention is not limited thereto. Rather,the present invention should be construed to include every and allmodifications, permutations, variations, adaptations, derivations,evolutions and embodiments that would occur to one having skill in thistechnology and being in possession of the teachings of the presentapplication. Accordingly, the present invention should be construed asbeing limited only by the following claims.

We claim:
 1. A support system for an array of parallel panels, saidsupport system including a vertical tilt brackets supported by anunderlying substrate, and a foldable support array, said foldablesupport array comprising: a) a connection interface for each saidvertical tilt bracket supporting at least two upper panel rails atconnection points; and, b) at least two diagonal supports arrangedbetween adjacent said upper panel rails, wherein said upper panel railsare parallel to each other in a deployed position, and said foldablearray is collapsible so that said upper panel rails and at least one ofsaid diagonal supports are substantially aligned in a package suitablefor motor road transport. 2-9. (canceled)
 10. A method of installing afoldable support array of upper panel rails and diagonal supports tosupport an array of parallel panels using on-site vertical tiltbrackets, where said bi-level support array is folded so that allelements are substantially aligned in a package suitable for motor roadtransport, said method comprising the steps of: a) unfolding saidsupport array and attaching to said on-site vertical tilt brackets; and,b) attaching diagonal supports between adjacent upper support rails. 11.The method of claim 10, further comprising the steps of: c) attachingpanels to said upper panel rails by screws passing through panel framesand into said upper panel rails.
 12. The method of claim 11, furthercomprising the step of: d) attaching auxiliary diagonal braces betweenat least one said vertical tilt bracket and at least one said upperpanel rail.
 13. The method of claim 12, further comprising the step of:e) attaching perpendicular lateral supports between two adjacent upperpanel rails. 14-15. (canceled)
 16. The method of claim 10, wherein saidfoldable support array further comprises lower support joists, saidlower support joists are rotatably connected to said upper panel railsto be unitarily foldable so that said upper panel rails and said lowersupport joists are substantially aligned with each other in a foldedposition in a package suitable for motor road transport, and said upperpanel rails and said lower support joists are substantiallyperpendicular to each other in a bi-level deployed position when mountedon said vertical tilt brackets.
 17. The method of claim 10, whereinadjacent said diagonal supports are slanted in opposite directions whenconnected between adjacent upper panel rails.
 18. The method of claim10, wherein at least two pairs of panel rails are connected to each saidvertical tilt bracket.
 19. The support system of claim 1, furthercomprising steel bearing washers at intersections between said diagonalsupports and said upper panel rails.
 20. The support system of claim 1,wherein said at least two diagonal supports are aligned opposite eachother.
 21. The support system of claim 20, further comprising: c) atleast one auxiliary diagonal support arranged from at least one saidupper panel rail to at least one said vertical tilt bracket.
 22. Thesupport system of claim 21, wherein said foldable support arraycomprises two sets of two interconnected panel rails.
 23. The supportsystem of claim 20, wherein said vertical tilt bracket comprises aC-channel, and at least one of said upper panel rails comprises twosubstantially parallel members connected by a median connecting member.24. The support system of claim 20, wherein said foldable support arrayfurther comprises lower support joists rotatably connected to said upperpanel rails and said foldable support array is collapsible, so that saidupper panel rails, said lower support joists and at least one of saiddiagonal supports are substantially aligned in a package suitable formotor road transport, and further wherein said upper panel rails andsaid lower support joists are substantially perpendicular to each otherin a bi-level deployed position mounted on said vertical tilt brackets.25. The support system of claim 24, further comprising steel bearingwashers between said upper panel rails and said lower support joists atintersections therebetween.
 26. The support system of claim 25, whereinsaid connection interface comprises an elongated longitudinal beamextending along an upper portion of said vertical tilt bracket.
 27. Thesupport system of claim 26, further comprising an arcuate supportextending from said vertical tilt bracket to said extended longitudinalbeam.
 28. The support system of claim 25, wherein said upper panelrails, said lower support joists, and said diagonal supports are steel.